Fan operation management

ABSTRACT

In various implementations, an air conditioner may manage operations of fan(s) of the air conditioner. The air conditioner may determine properties of the air conditioner (e.g., ambient temperature and/or pressure of a portion of the air conditioner) and determine setting(s) for fan(s) and/or a crankcase heater based on the determined properties.

TECHNICAL FIELD

The present disclosure relates to fan operation management.

BACKGROUND

At low ambient temperatures, fans that provide air to the condenser of an air conditioner may cycle on and off. Cycling the fans may cause mechanical wear on the fans and/or may cause instability due to changes in pressures in the air conditioner and/or portions thereof.

SUMMARY

In various implementations, an air conditioner may include more than one fan. The fan(s) may include more than one setting, and the mass flow rate of the air provided by a fan may change based on the setting of the fan. The air conditioner may alter the setting of the fan(s) based on properties of the air conditioner. By controlling the setting of the fan(s), mechanical wear of the air conditioner may be reduced and/or pressure fluctuations in the air conditioner or portions thereof may be controlled. In some implementations, the setting of the fan(s) may maintain a pressure range in the air conditioner or portions thereof.

In various implementations, an air conditioner system may include more than one compressor, one or more fans, a memory, and a processor. At least one of the fans may include one or more first fans, which include a high setting and one or more lower settings. The memory may store a fan management module and a processor of the system may execute the fan management module. The fan management module may receive a request for operation of an air conditioner and determine a temperature proximate at least a portion of the air conditioner. The fan management module may determine whether the determined temperature is less than a first predetermined low ambient temperature. If the determined temperature is less than the first predetermined low ambient temperature, the fan management module may allow restriction of the operation of at least one of the fans. If the determined temperature is less than the first predetermined low ambient temperature, the fan management module may allow operation of at least one of the first fans.

Implementations may include one or more of the following features. One or more lower settings of the first fans may include a first low setting, a second low setting, and/or a third low setting. The second low setting may be lower than the first low setting (e.g., associated with a slower fan speed). The third low setting may be lower than the second low setting (e.g., associated with a slower fan speed). The fan management module may determine an operation of the compressors and determine whether the determined temperature is less than a second predetermined low ambient temperature. The second predetermined low ambient temperature may be less than the first predetermined low ambient temperature. If the determined temperature is less than the second predetermined low ambient temperature and if the determined compressor operation includes a full load operation, the fan management module may allow operation of at least one first fan at the first low setting. If the determined temperature is less than the second predetermined low ambient temperature and if the determined compressor operation comprises a part load operation, the fan management module may allow operation of at least one first fan at the third low setting. If the determined temperature is less than the first predetermined low ambient temperature and the determined temperature is not less than the second predetermined low ambient temperature and the determined compressor operation comprises a part load operation, the fan management module may allow operation of at least one first fan at the second low setting. The fan management module may allow operation of one of the first fans and restrict operation of the other fans, in some implementations. The fan management module may determine an operation of the compressors, and allow operation of at least one of the fans at the high setting if the determined compressor operation comprises a full load operation. In some implementations, the fan management module may determine an operation of the compressors, and allow operation of at least one of the fans at the second low setting if the determined compressor operation comprises a part load operation. In some implementations, the fan management module may determine whether a compressor operation comprises a part load operation, and allow operation of one or more crankcase heaters associated with one or more compressors in which operation is restricted, if the compressor operation comprises a part load operation. The fan management module may determine whether the determined temperature is less than a second predetermined low ambient temperature, which is less than the first predetermined low ambient temperature. If the determined temperature is less than the second predetermined low temperature, the fan management module may allow operation of one or more crankcase heaters associated with one or more compressors of the air conditioner.

In various implementations, a temperature may be determined proximate at least a portion of an air conditioner and a determination may be made whether the determined temperature is less than a first predetermined low ambient temperature. If the determined temperature is less than the first predetermined low ambient temperature, operation of at least one fan of the air conditioner may be restricted and operation of at least one of the fans of the air conditioner may be allowed.

Implementations may include one or more of the following features. One or more fans of the air conditioner may include a high setting and at least one low setting. A determination may be made whether the determined temperature is less than a second predetermined low ambient temperature. If the determined temperature is less than the second predetermined low ambient temperature, then operation of at least one of the fans may be allowed at one of the low settings. In some implementations, an operation of compressors of the air conditioner may be determined, and a determination may be made whether the determined temperature is less than a second predetermined low ambient temperature. Operation of at least one of the fans may be allowed at the high setting, if the determined compressor operation includes a full load operation, and if the determined temperature is less than the first predetermined low ambient temperature and not less than the second predetermined low ambient temperature. In some implementations, an operation of compressors of the air conditioner may be determined. Operation of at least one of the fans of the air conditioner may be allowed at one of the low settings, if the determined compressor operation comprises a part load operation, and if the determined temperature is less than the first predetermined low ambient temperature. In some implementations, operation of one or more crankcase heaters associated with one or more of the compressors in which operation is restricted may be allowed, if the determined operation of the compressors comprises a part load operation, and if the determined temperature is less than the first predetermined low ambient temperature. A determination may be made whether the determined temperature is less than a second predetermined low ambient temperature, which is less than the first predetermined low temperature. Operation of one or more crankcase heaters associated with one or more of the compressors of the air conditioner may be allowed, if the determined temperature is less than the second predetermined low ambient temperature. In some implementations, an operation of compressors of the air conditioner may be determined. Operation of one or more crankcase heaters associated with one or more of the compressors in which operation is restricted may be allowed, if the determined temperature is less than the first predetermined low ambient temperature and the determined operation of the compressors comprises a part load operation.

In various implementations, a temperature of a portion of an air conditioner may be determined and a predetermined low ambient temperature may be retrieved from a memory of a computer. A determination may be made whether the determined temperature is less than the retrieved predetermined low ambient temperature. If the determined temperature is less than the predetermined low ambient temperature: operation of at least one fan of the air conditioner may be restricted; and operation of at least one fan of the air conditioner may be allowed at a setting to maintain a pressure of a portion of the air conditioner in a predetermined pressure range.

Implementations may include one or more of the following features. The setting to maintain the pressure of the portion of the air conditioner may be determined based at least partially on the determined temperature. The setting to maintain the pressure of the portion of the air conditioner may be determined based at least partially on the determined temperature, a number of fans included in the air conditioner, a number of modes of operation of each fan of the air conditioner, and/or the predetermined pressure range. In some implementations, a determination may be made whether an operation of compressors of the air conditioner comprises a part load operation. Operation of one or more crankcase heaters associated with compressors in which operation is restricted may be allowed, if the operation of compressors comprises a part load operation and if the determined temperature is less than the retrieved predetermined low ambient temperature.

The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the implementations will be apparent from the description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure and its features, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates an implementation of an example air conditioner.

FIG. 2 illustrates an implementation of an example process for managing fan operations.

FIG. 3 illustrates an implementation of an example process for managing fan operations.

FIG. 4 illustrates an implementation of an example process for managing fan operations.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

In various implementations, an air conditioner may operate at a variety of ambient conditions. In some implementations, a user may request the delivery of cool air during low ambient temperatures (e.g., below approximately 65 degrees Fahrenheit, below approximately 62 degrees Fahrenheit, and/or from approximately 62 degrees Fahrenheit to approximately 45 degrees Fahrenheit). When the air conditioner operates in response to a request at low ambient temperatures, the air conditioner may cycle fans on and off to provide the appropriate cool air to a location, as requested by the user. Cycling fans on and off may increase the mechanical wear on the fan (e.g., when compared with fan operation in ambient temperatures above low ambient temperatures). In some implementations, operation of the air conditioner at low ambient temperatures may cause pressure fluctuations in the air conditioner or portions thereof, which may cause less stability (e.g., due to pressure fluctuations) in the air conditioner (e.g., when compared with an air conditioner operating in ambient temperatures above low ambient temperatures).

In some implementations, the air conditioner may control the fan speed during operations at ambient temperatures that are in a low ambient temperature range (e.g., below a first and/or a second predetermined ambient temperature and/or between a first predetermined ambient temperature and a second predetermined ambient temperature). For example, fan(s) may be restricted and/or allowed to operate. The air conditioner may determine an appropriate fan setting of the fans allowed to operate, when a fan has more than one fan setting. In some implementations, the air conditioner may control crank case heater operation during operations at ambient temperatures that are in a low ambient temperature range.

FIG. 1 illustrates an implementation of an example air conditioner 100. The air conditioner may include components such as a condenser 110, compressor A 120, compressor B 130, and evaporator 140. As illustrated, each compressor 120, 130 may include a crank case heater 125, 135. Lines (e.g., tubing) may couple various components and allow refrigerant to flow in and/or out of various components of the air conditioner 100.

Fans 160, 170 may cause air to flow through the condenser 110 and/or the evaporator 140. The air conditioner 100 may include more than one fan to provide air flow to the condenser 110 and/or more than one fan to provide air flow to the evaporator 140. As illustrated, the air conditioner 100 may include a first condenser fan 162, a second condenser fan 164, and a third condenser fan 166 to provide air flow to the condenser 110 and a first evaporator fan 172, a second evaporator fan 174, and a third evaporator fan 176 to provide air flow to the evaporator 140.

The condenser 110 may include an appropriate condenser. In some implementations, the condenser 110 may be a microchannel condenser (e.g., condenser with a channel size less than approximately 1 mm). Microchannel condensers may be sensitive to operating conditions during operation of the air conditioner (e.g., when compared with other condensers (e.g., condenser with tube size greater than 5 mm)). For example, microchannel condensers may be sensitive to refrigerant charge (e.g., a level of refrigerant in the system). When a microchannel condenser has a refrigerant charge greater than a maximum operating charge, the pressure in the microchannel condenser may become elevated due to the refrigerant capacity size difference between the microchannel condenser and the evaporator. In some implementations, a pressure of the condenser may be based at least partially on an operation of the fan(s) that provide air to the condenser (e.g., outdoor fans). The high pressures (e.g., pressures greater than approximately 615 psi, with a refrigerant that includes R-410A refrigerant) may cause mechanical failure, including prefailure events, such as excessive wear on parts and/or high-pressure switch activations. Thus, the air conditioner may control the pressure in the system to manage stability and/or inhibit mechanical failure of the air conditioning system. For example, by managing operation(s) of the fan(s) that provide air to the condenser, pressure in the system (e.g., the condenser) may be managed to manage stability and/or inhibit mechanical failure of the air conditioning system.

Fans 160 may provide airflow to the condenser 110, and fans 170 may provide airflow to the evaporator 140. The fan(s) 160, 170 may include any appropriate number of fans, such as one, two, three, or four fans. A fan 160, 170 may be any appropriate type of fan, such as an axial fan. A fan 160, 170 may include more than one fan setting. For example, the fan may be a multi-speed fan and/or a variable speed fan. In some implementations, a fan may include a high setting and one or more low settings. The settings may be associated with the speed at which the impeller of the fan rotates. For example, fan settings may include a high setting, a first low setting, and a second low setting. The second low setting may be associated with a lower fan speed than the first low setting. For example, a fan may allow operation at 800 RPM (rotations per minute), 650 RPM, and/or 330 RPM. In some implementations, a fan may include a low setting and more than one high setting.

The compressors 120, 130 of the air conditioner may include any appropriate arrangement of compressors (e.g., in separate circuits and/or in parallel circuits). The compressors 120, 130 may include a tandem compressor system. The tandem compressor system may allow more than one compressor (e.g., compressor A 120 and compressor B 130) to share discharge lines and suction lines.

Compressor A 120 and/or compressor B 130 may include single stage and/or multi-stage (e.g., more than one stage) compressors. Compressor A 120 and compressor B may be independently operable, in some implementations. For example, compressor A 120 may be allowed to operate and compressor B may be restricted from operation.

Compressor A 120 and/or compressor B 130 may include crankcase heaters 125, 135. The crankcase heaters may include any appropriate crankcase heater. For example, the crankcase heater may be a variable wattage crankcase heater, an on/off heater, and/or a multi-stage heater. A crankcase heater may be disposed in a housing of the compressor, in some implementations. A crankcase heater may provide heat to a portion of a compressor (e.g., the crankcase of a compressor). By delivering heat to the crankcase of the compressor, the crankcase heater may inhibit refrigeration migration, inhibit mixing between the refrigerant and the crankcase oil, and/or inhibit condensation of refrigerant in the crankcase. For example, when a compressor has been turned off for a period of time, the temperature of the refrigerant in the compressor may be low and so the crankcase heater may be utilized to increase the temperature of the refrigerant in the crankcase and inhibit mixing with crankcase oil. In various implementations, the air conditioner may utilize the crankcase heater during operations at ambient temperatures in a low ambient temperature range (e.g., below approximately 65 degrees Fahrenheit, below approximately 62 degrees Fahrenheit, and/or from approximately 62 degrees Fahrenheit to approximately 45 degrees Fahrenheit). In some implementations, the range of temperatures included in a low ambient temperature range may be determined based on the components of the air conditioner, manufacturer(s), field technician(s), user(s), and/or any other appropriate entity.

The air conditioner may include an expansion device 150, as illustrated. The expansion device may include any device that at least partially expands refrigerant passing through the device. For example, the expansion device 150 may include a thermal expansion valve, an orifice, an air conditioner capillary tube (e.g., a tube with a smaller cross-sectional area than other lines in the system and/or a tube with a diameter of approximately 0.02 inches to approximately 0.09 inches) and/or an electronic expansion valve.

A controller 180 (e.g., a computer) may be coupled (e.g., communicably, such as by wires or linked by Wi-Fi) to component(s) of the air conditioner 100 and control various operations of the component(s) and/or system. For example, the controller 180 may include modules (e.g., instructions), such as an operation module and/or management module, stored in a memory of the controller and executable by a processor of the controller, to perform various operations of the air conditioner 100. The operation module may control operations of the air conditioner 100, such as receiving requests for operation, determining whether to respond to requests for operation, operating various components (e.g., compressors, reversing valves, and/or expansion valves), etc. The management module may control operation and/or restriction of operation of one or more components of the air conditioner 100, such as fan(s), crankcase heater(s), compressor(s), etc. For example, the management module may determine properties of the air conditioner (e.g., temperature proximate a portion of the air conditioner such as ambient temperature and/or pressure of at least a portion of the air conditioner), retrieve one or more predetermined values for properties (e.g., predetermined low ambient temperature(s)), determine settings for crankcase heater(s) and/or compressor(s), allow crankcase heater(s) and/or compressor(s) to operate, restrict crankcase heater and/or compressor operation(s), allow crankcase operation, and/or any other appropriate operation.

The controller 180 may include a memory that stores the modules (e.g., instructions) and/or other data. For example, the memory may store predetermined property values (e.g., predetermined low ambient temperature value(s), predetermined low ambient temperature range(s), predetermined low compressor temperature(s), predetermined operating pressure(s), and/or predetermined operating pressure range(s)); associations between determined properties of the air conditioner and compressor operation(s) and/or crankcase heater operation(s); and/or other appropriate data.

Although FIG. 1 illustrates an implementation of an air conditioner, other implementations may be utilized as appropriate. For example, the air conditioner may include and/or not include any components, as appropriate. The air conditioner may not include an expansion device. The air conditioner may include more than two compressors (e.g., a tandem compressor with four compressors). The air conditioner may include one compressor. In some implementations, the expansion device may include more than one expansion device. The air conditioner may be a heat pump and may include a reversing valve to allow cooling and heating operations. In some implementations, the air conditioner may include one or more fans (e.g., one or more fans associated with the evaporator and/or one or more fans associated with the condenser). For example, a fan may include a multi-speed fan (e.g., a two-stage fan, a three-stage fan, and/or a variable speed fan) capable of adjusting an amount of air (e.g., volumetric flow rate and/or mass flow rate). The fans 160 and/or the fans 170 may include a different number or the same number of fans. The fans 160 and/or the fans 170 may include more than three fans. In some implementations, the fans 160 and/or the fans 170 may include less than three fans. In some implementations, one or more of the compressors may not include a crankcase heater.

In some implementations, a portion of the air conditioner 100 may be disposed outside a building (e.g., an “outdoor portion” on the ground proximate a building and/or on a roof of the building) and a portion of the air conditioner 100 may be disposed inside the building (e.g., an “indoor portion”). For example, the outdoor portion may include condenser 110 and fans 160 and the indoor portion may include evaporator 140 and fans 170. In some implementations, such as a rooftop unit, the condenser 110, fans 160, compressor A 120, crankcase heater 125, compressor B 130, crankcase heater 135, evaporator 140, fans 170, and the expansion device 150 may be disposed in the outdoor portion. The outdoor and/or indoor portion may be at least partially disposed in housing(s).

During a cooling cycle of the air conditioner 100, cool air may be provided by blowing air (e.g., from fans 170) at least partially through evaporator 140. The evaporator 140 may evaporate liquid refrigerant in the evaporator. The evaporator may remove heat from the air to generate cool air, and the cool air may be provided to a location (e.g., via ducting). The gaseous refrigerant may exit the evaporator 140, then may be compressed by compressor A 120 and compressor B 130, and delivered to a condenser 110. The condenser 110 may condense the gaseous refrigerant by blowing air (e.g., from fans 160) at least partially through the condenser 110 to remove heat from the gaseous refrigerant.

During air conditioner operation at ambient temperatures in a predetermined low ambient temperature range. To inhibit mechanical wear and/or pressure fluctuations (e.g., outside a predetermined operational pressure range), the air conditioner may control fan operations and/or crankcase heater operations.

FIG. 2 illustrates an implementation of an example process 200 for managing fan operations. A request for operation of an air conditioner may be received (operation 210). For example, a user may request that cool air be delivered to a location. The user may specify parameters (e.g., temperature setpoint and/or humidity setpoint) in the request. The controller (e.g., a module of the controller) of the air conditioner may receive the request.

A determination may be made whether to allow operation of the air conditioner (operation 220). For example, the request may include parameter(s). The controller (e.g., a module of the controller) may determine whether to allow operation of the air conditioner based at least partially on the parameter(s) in the request. For example, the request may specify that a temperature at a location be maintained at approximately 75 degrees Fahrenheit. The controller may determine that the location is already at approximately 75 degrees Fahrenheit and restrict operation of the air conditioner. The controller may determine that the location is above 75 degrees and allow operation of the air conditioner to provide cool air to the location. Thus, the temperature of the location may be reduced.

A property of the air conditioner may be determined (operation 230). For example, a temperature proximate at least a portion of the air conditioner (e.g., ambient temperature and/or temperature proximate an outdoor condenser) may be determined. The air conditioner may include sensors (e.g., disposed such that a property at a predetermined location may be measured) that are coupled to the controller such that a property can be determined by the controller (e.g., a module of the controller that is executed by a processor of the controller).

Setting(s) of one or more fans of the air conditioner may be determined based at least partially on the determined property and the determination of whether to allow operation of the air conditioner (operation 240). For example, settings for fans that provide airflow to the condenser and/or to an outdoor portion of the air conditioner may be determined. The determined property may be compared to a retrieved property value (e.g., predetermined operational property value, predetermined low property value, and/or other appropriate values for comparisons) to determine (e.g., using a module of the controller) whether to alter a fan setting. In some implementations, a table of associations may be retrieved to facilitate a determination of the setting that should be allowed for a fan. For example, a table of associations may specify a fan setting at a determined property (e.g., temperature and/or pressure).

Operation of the fan(s) may be allowed and/or restricted based at least partially on the determined setting(s) (operation 250). For example, the controller may transmit signal(s) to one or more of the fans to allow and/or restrict operation based on the determined settings. For example, if a fan setting is determined to be off, then the controller (e.g., a module of the controller that is stored in a memory of the controller and executed by a processor of the controller) may transmit a signal to a fan to restrict operation of the fan. If a fan setting is determined to be on and at a first low setting, the controller may transmit a signal to allow operation of the fan at the first low setting.

Process 200 may be implemented by various systems, such as system 100. One or more of the operations or portions thereof may be stored in a memory of the system and/or executed by a processor of the system (e.g., controller). In addition, various operations may be added, deleted, and/or modified. For example, more than one property of the air conditioner may be determined. Setting(s) of the fan(s) may be determined based at least partially on one or more of the determined properties. In some implementations, a property of the air conditioner, such as pressure, may be determined (e.g., in addition to and/or instead of a temperature). In some implementations, the determined settings of the fans comprise settings for fans that provide airflow to the condenser and/or the outdoor portion of the air conditioner. In some implementations, the air conditioner may include at least one multi-speed fan, with a high setting and one or more lower settings. When an operation of a fan is restricted, a fan may be restricted from operating at the high setting and allowed to operate at a low setting and/or be restricted from operation (e.g., turned off).

In some implementations, the temperature (e.g., ambient temperature) proximate at least a portion of the air conditioner may be determined. The controller may select a fan setting based on a received request for operation when the determined temperature is not in a predetermined low ambient temperature range (e.g., less than a predetermined low ambient temperature, such as 62 degrees Fahrenheit; and/or from approximately 45 degrees Fahrenheit to approximately 62 degrees Fahrenheit). In some implementations, if the determined temperature is in a predetermined low ambient temperature range (e.g., the determined temperature may be compared to a predetermined low ambient temperature range retrieved from a memory of the controller), the controller may determine the fan setting based on a low ambient temperature protocol.

In some implementations, the controller may retrieve a low ambient temperature protocol from a memory of the air conditioner. The low ambient temperature protocol may include formulas that relate determined temperatures, requests for operation, and/or fan speeds; association tables that relate determined temperatures, requests for operation, and/or fan speeds; and/or other appropriate ways to determine a fan speed based at least partially on determined temperature, determined pressure, and/or a request for operation. For example, a low ambient temperature protocol may determine fan speed based on a formula when a compressor operation comprises a full load, such as, but not limited to the following formula:

Fan  speed = 0.000208328887205324  * (Determined  Temperature)² + 0.000869569932420933  * (Determined  Temperature) + 0.29318046545814

In some implementations, a low ambient temperature protocol may determine fan speed based on a formula when a compressor operation comprises a full load, such as, but not limited to the following formula:

Fan speed=0.00021*(Determined Temperature)+0.00087*(Determined Temperature)+0.29

In some implementations, a low ambient temperature protocol may determine fan speed based on a formula when a compressor operation comprises a part load, such as, but not limited to the following formula:

Fan  speed = −0.000499375955505381  * (Determined  Temperature)² + 0.0127918634171138  * (Determined  Temperature) + 0.158510704636291

In some implementations, a low ambient temperature protocol may determine fan speed based on a formula when a compressor operation comprises a part load, such as, but not limited to the following formula:

Fan speed=−0.00005*(Determined Temperature)+0.013*(Determined Temperature)+0.16

Utilization of the fan speed may maintain a pressure of the air conditioner or portion thereof in a predetermined pressure range. For example, the predetermined pressure range may be between the liquid line pressure switch setting and the high-pressure switch setting, in some implementations. In some implementations, the predetermined pressure range may be based on steady state operational pressures of the air conditioner at temperatures above a predetermined low ambient temperature range. In some implementations, the predetermined pressure range may be based on maintaining compressor operation in a predetermined efficiency range (e.g., a middle section of a compressor efficiency map).

In some implementations, the fan speed determined by the controller may be based at least partially on the request for operation. Based on the request for operation, the air conditioner may determine an operation of the compressors. For example, the compressor(s) may be operated at part load (e.g., one or more compressors may be restricted and one or more compressors may be allowed to operate) or full load (e.g., each compressor of the air conditioner may be allowed to operate) based on the request for operation. The fan setting may be determined based at least partially on whether the compressor(s) of the air conditioner are operated at part load and/or full load. The fan may include one or more settings such as a high setting and one or more low settings. The high setting may be associated with a higher impeller speed than the low settings. The low settings may include a first low setting and a second low setting, which is associated with a lower impeller speed than the first low setting. When the compressor operation includes a full load operation and a determined temperature is less than a predetermined low ambient temperature, a fan may be allowed to operate at a high setting. When the compressor operation includes a part load operation and a determined temperature is less than a predetermined low ambient temperature, a fan may be allowed to operate at one of the low settings (e.g., a second low setting). In some implementations, if the determined temperature is less than a second predetermined low ambient temperature, which is less than the first predetermined low ambient temperature, and when the compressor operation includes a full load operation, a fan may be allowed to operate at a lower setting (e.g., a first low setting). In some implementations, if the determined temperature is less than a second predetermined low ambient temperature and when the compressor operation includes a part load operation, a fan may be allowed to operate at a lower setting (e.g., a third low setting, which is associated with a lower impeller speed than the second low setting).

In some implementations, the low temperature protocol may include an association table to facilitate determination (e.g., by a controller) of a fan setting based on temperature and/or compressor operation, such as but not limited to:

TABLE 1 example low temperature protocol association table Fan Speed of Fan Compressor Determined Temperature allowed to operate Full Load Below first predetermined High Setting low ambient temperature Full Load Below second predetermined First Low Setting low ambient temperature Part Load Below first predetermined Second Low Setting low ambient temperature Part Load Below second predetermined Third Low Setting low ambient temperature

TABLE 2 example low temperature protocol association table Fan Speed of Fan Compressor Determined Temperature allowed to operate Full Load Below 62 degrees F. >650 RPM Full Load Below 45 degrees F.  650 RPM Part Load Below 62 degrees F. >330 RPM Part Load Below 45 degrees F.  330 RPM

In some implementations, a crankcase heater operation may be managed using the low temperature protocol. The crankcase heater may be allowed to operate when a determined temperature (e.g., ambient temperature) is in a low ambient temperature range. For example, when a determined temperature is less than a first predetermined ambient temperature and when compressor(s) are operated at part load, a crankcase heater associated with a compressor restricted from operation may be allowed to operate. When a determined temperature is less than a first predetermined ambient temperature and when compressor(s) are operated at full load, a crankcase heater may be restricted from operation. In some implementations, when a determined temperature is less than a second predetermined ambient temperature (e.g., less than approximately 45 degrees Fahrenheit), operation of a crankcase heater may be allowed in each of the crankcase heaters (e.g., while the compressor is allowed to operate and/or restricted from operation).

In some implementations, when the compressor(s) are operated at part load, the crankcase heater may be allowed to operate when at least one fan of the air conditioner is restricted. The crankcase heater may be restricted from operating when more than one fan of the air conditioner is allowed to operate.

FIG. 3 illustrates an implementation of an example process 300 for managing fan operations. A request for operation of an air conditioner may be received (operation 310). For example, a user may transmit a request via a thermostat for operation of an air conditioner. The controller (e.g., a module of the controller) may receive the request. The request may include parameters, such as a setpoint temperature.

A temperature proximate the air conditioner or portions thereof may be determined (operation 320). For example, a temperature proximate an outdoor condenser may be determined. The determined temperature may be approximately equal to the ambient temperature. In some implementations, such as a rooftop air conditioner, a temperature proximate a housing of the air conditioner may be determined. A sensor (e.g., thermocouple) of the air conditioner may be coupled to the controller to allow the controller to determine a temperature proximate a portion of the air conditioner, such as the ambient temperature.

One or more predetermined low ambient temperatures may be retrieved (operation 330). For example, a memory of a controller may store one or more predetermined low ambient temperatures. In some implementations, predetermined low ambient temperatures may include a first predetermined low ambient temperature and a second predetermined low ambient temperature, which is lower in temperature than the first predetermined low ambient temperature. For example, the first predetermined low ambient temperature may be approximately 65 degrees Fahrenheit, approximately 62 degrees Fahrenheit, and/or approximately 60 degrees Fahrenheit. A second predetermined low ambient temperature may be approximately 48 degrees Fahrenheit, approximately 45 degrees Fahrenheit, and/or approximately 43 degrees Fahrenheit, for example.

The determined temperature may be compared to one or more of the retrieved predetermined low ambient temperatures (operation 340). For example, the controller may determine if the determined temperature is lower than the predetermined low ambient temperature(s). In some implementations, the controller may determine if the determined temperature is between two of the retrieved predetermined low ambient temperatures.

Setting(s) of one or more of the fans of the air conditioner may be determined at least partially based on the comparison (operation 350). For example, if a determined temperature is greater than the predetermined low ambient temperature(s), then the controller may determine a setting of a fan based at least partially on the received request for operation. If a determined temperature is less than at least one of the predetermined low ambient temperatures, then a controller may utilize a low ambient temperature protocol to determine a setting of fan(s) of the air conditioner. The low ambient temperature protocol may include determining setting(s) for fan(s), by, for example, allowing the controller to retrieve a formula and/or a table of associations to determine a fan speed based at least partially on an ambient temperature. The fans for which settings may be determined may include the fans proximate a location in which the determined temperature is measured, the fans disposed in an outdoor portion of the air conditioner, and/or the fans that provide airflow to the condenser, in some implementations.

Operation of the fan(s) may be allowed and/or restricted based on the determined setting(s) (operation 360). For example, the setting(s) of the fan may include turning the fan off and/or allowing fan operation at a speed (e.g., according to the setting). If the setting of the fan includes turning the fan off, then operation of the fan may be restricted. If a setting of the fan includes operation of a fan at a low speed, for example, then operation of the fan may be allowed at the low speed. In some implementations, one fan may be allowed to operate while other fans are restricted from operating. In some implementations, all the fans of the air conditioner may be operated or restricted.

Process 300 may be implemented by various systems, such as system 100. One or more of the operations or portions thereof may be stored in a memory of the system and/or executed by a processor of the system (e.g., controller). In addition, various operations may be added, deleted, and/or modified. In some implementations, process 300 may be performed in combination with other processes such as process 200. For example, more than one temperature proximate the air conditioner may be determined. The determined temperature(s) may be compared to the retrieved low ambient temperature(s). In some implementations, predetermined low temperature range(s) may be retrieved (e.g., from a memory of the controller) and utilized in a comparison of the determined temperature to the retrieved low ambient temperature(s) (e.g., temperature ranges).

In some implementations, an air conditioner may include more than one fan. One or more of the fans may include a high setting and one or more low settings (e.g., a first low setting and a second low setting, which is associated with a slower impeller speed than the first low setting). The settings may be associated with impeller fan speeds. When a setting of the fan is determined (e.g., by the controller), a high setting, one of the low settings, and/or an off setting may be selected. For example, when a determined temperature is less than a first predetermined low ambient temperature, then a controller (e.g., a module of a controller) may allow a first low setting for one of the fans and restrict operation of the other fans. If the determined temperature is less than a second predetermined low ambient temperature (e.g., less than the first predetermined low ambient temperature), then the controller may allow a second low setting for one of the fans and restrict operation of the other fans.

In some implementations, the controller may determine whether to allow operation of a crankcase heater. A determination of whether to allow operation of a crankcase heater may be based on the determined temperature. In some implementations, a determination of whether to allow operation of the crankcase heater may be based at least partially on the load of the compressor(s) and/or the setting of the fan. For example, when the compressor(s) operate at a part load, the crankcase heater may be allowed to operate when at least one of the fans is restricted from operation. A crankcase heater may be restricted from operating when more than one fan is and/or all of the fans are allowed to operate, in some implementations. In some implementations, when a determined temperature is less than a first predetermined low ambient temperature and when the compressor(s) operate at part load, the crankcase heater associated with compressor(s) restricted from operating may be allowed to operate. When a determined temperature is less than a first predetermined low ambient temperature (e.g., less than the first low ambient temperature) and when the compressor(s) operate at full load, the crankcase heater may be restricted from operating. When a determined temperature is less than a second predetermined low ambient temperature (e.g., less than the first low ambient temperature) and when the compressor(s) operate at part load, the crankcase heater associated with compressor(s) restricted from operating may be allowed to operate. In some implementations, operation of crankcase heaters associated with compressors allowed to operate, may be allowed, for example when a determined temperature is less than the second predetermined low ambient temperature.

In some implementations, each compressor may include a crankcase heater. When a controller determines whether to allow operation of a crankcase heater, the controller may allow each crankcase heater to have the same operation (e.g., on or off) and/or different operations. For example, when compressors are allowed to operate at part load, the crankcase heater on the compressor that is restricted from operation may be allowed to operate. When compressors are allowed to operate at part load and all of the fans are allowed to operate, the crankcase heaters may be restricted from operation.

FIG. 4 illustrates an implementation of an example process 400 for managing fan operations. A request for operation of an air conditioner may be received (operation 410). For example, a user may transmit a request for operation of an air conditioner (e.g., to provide cool air to a location). The request may be received by a module, which is stored in a memory of the controller and executed by the processor of the controller.

A temperature proximate a portion of the air conditioner may be determined (operation 420). For example, the air conditioner may include one or more sensors to determine temperature. The sensors may transmit a measurement to the controller and a temperature may be determined. The temperature may be measured at one or more portions of the air conditioner and utilized and/or aggregated.

One or more predetermined low ambient temperatures nay be retrieved (operation 430). The predetermined low ambient temperature(s) may be stored in a memory of the air conditioner (e.g., controller). The predetermined low ambient temperature(s) may include a value or range of values.

The determined temperature may be compared to one or more of the retrieved predetermined low ambient temperatures (operation 440). For example, the controller may determine if the determined temperature has a value less than and/or greater than one or more of the retrieved predetermined low ambient temperature(s). For example, the controller (e.g., a module executed by the processor of the controller) may determine if the determined temperature is less than a predetermined low ambient temperature.

If the determined temperature is less than at least one of the predetermined low ambient temperatures, operation of at least one of the fans may be restricted and operation of at least one of the fans may be allowed, where the setting of the fan maintains a pressure of a portion of the air conditioner in a predetermined pressure range (operation 450). For example, a predetermined operational pressure range may be retrieved from a memory of the controller. The predetermined operational pressure range may include values that are less than the pressure at which a high-pressure switch of the air conditioner is triggered and/or greater than the liquid refrigerant pressure in the air conditioner. For example, the predetermined operational pressure range may be greater than approximately 30 psi and/or less than approximately 650 psi. Settings of fans allowed to operate may be determined by the controller to allow a pressure of a portion of the air conditioner to be maintained in the predetermined operational pressure range. For example, a formula may be retrieved that allows a fan setting to be determined based on determined temperature(s).

Process 400 may be implemented by various systems, such as system 100. One or more of the operations or portions thereof may be stored in a memory of the system and/or executed by a processor of the system (e.g., controller). In addition, various operations may be added, deleted, and/or modified. In some implementations, process 400 may be performed in combination with other processes such as process 200 and/or process 300. For example, more than one pressure of a portion of the air conditioner may be determined. The determined pressures may be compared to one or more of the retrieved predetermined pressure(s). In some implementations, if the determined pressure is within a predetermined operational pressure range, then setting(s) of the fan(s) may be determined based at least partially on the received request for operation. If the determined pressure is not within a predetermined operational pressure range, then setting(s) of the fan(s) may be based at least partially on a low ambient temperature protocol. Operation of the fan(s) may be allowed and/or restricted based at least partially on the determined setting(s). For example, the controller may transmit signals to the fans based on the determined settings and fan operations may be allowed and/or restricted.

In some implementations, operation of a crankcase heater and/or one or more portions of a low ambient temperature protocol may be utilized to maintain a pressure of at least a portion of the air conditioner in a predetermined pressure range. For example, when a pressure is greater than a retrieved predetermined pressure and a determination is made to allow an ambient temperature protocol, a crankcase heater may be allowed to operate and/or may be restricted from operation. For example, a determination of whether to allow a crankcase heater operation may be based at least partially on a setting of the compressor (e.g., full load and/or partial load) and/or setting(s) of fan(s).

In some implementations, the setting(s) of the fans may be determined at least partially based on the determined temperature and/or the determined pressure. For example, the determined temperature may be compared to predetermined temperature(s) retrieved from a memory of the air conditioner and/or determined pressure may be compared to predetermined pressure(s) retrieved from a memory of the air conditioner. The comparisons may be utilized to determine settings of the fans. A determination of whether to determine settings of the fans based on a low ambient temperature protocol may be based at least partially on the comparisons. For example, if the determined temperature is less than a predetermined low ambient temperature range and/or the determined pressure is outside a predetermined operational pressure range, then a low temperature protocol may be utilized to determine settings of the fans.

Although a specific controller has been described in FIG. 1, the controller may be any appropriate computer or other programmable logic device. The controller may include a processor that executes instructions (e.g., modules) and manipulates data to perform operations of the controller. Processor may include a programmable logic device, a microprocessor, or any other appropriate device for manipulating information in a logical manner and memory may include any appropriate form(s) of volatile and/or nonvolatile memory, such as RAM and/or Flash memory.

In addition, various software may be stored on the memory. For example, instructions (e.g., operating systems and/or other types of software), an operation module and/or a fan management module may be stored on the memory. The operation module may operate the air conditioner and/or components thereof during normal operations (e.g., operations in which the system operates based at least partially on user requests for operation). The fan management module may perform one or more of the operations in processes 200, 300, 400, portions thereof, and/or combinations thereof. For example, the fan management module may determine properties; retrieve predetermined property values and/or ranges of values; compare values; determine fan settings and/or crankcase heater settings; determine whether to allow low ambient temperature protocols; determine whether to retrieve a table of associations and/or formulas; and/or other operations.

In some implementations, modules may be combined, such as into a single module or multiple modules. Operation modules and/or fan management modules may be distinct modules. In an implementation, operation modules and/or fan management modules may include various modules and/or sub-modules.

A communication interface may allow the controller to communicate with components of the heat pump, other repositories, and/or other computer systems. The communication interface may transmit data from the controller and/or receive data from other components, other repositories, and/or other computer systems via network protocols (e.g., TCP/IP, Bluetooth, and/or Wi-Fi) and/or a bus (e.g., serial, parallel, USB, and/or FireWire). Operations of the heat pump stored in the memory may be updated and/or altered through the communication via network protocols (e.g., remotely through a firmware update and/or by a device directly coupled to the controller).

The controller may include a presentation interface to present data to a user, such as though a monitor and speakers. The presentation interface may facilitate receipt of requests for operation from users.

A client (e.g., control panel in field or building) may allow a user to access the controller and/or instructions stored on the controller. The client may be a computer system such as a personal computer, a laptop, a personal digital assistant, a smart phone, or any computer system appropriate for communicating with the controller. For example, a technician may utilize a client, such as a tablet computer, to access the controller. As another example, a user may utilize a client, such as a smart phone, to access the controller and request operations.

Although FIG. 1 provides one example of controller that may be used with the disclosure, controller can be implemented through computers such as servers, as well as a server pool. For example, controller may include a general-purpose personal computer (PC) a Macintosh, a workstation, a UNIX-based computer, a server computer, or any other suitable device. In some implementations, a controller may include a programmable logic device. For example, the controller may be mounted to a wall of a location in which air conditioning may be provided. According to one implementation, controller may include a web server. Controller may be adapted to execute any operating system including UNIX, Linux, Windows, or any other suitable operating system. Controller may include software and/or hardware in any combination suitable to provide access to data and/or translate data to an appropriate compatible format.

Various implementations of the systems and techniques described herein can be realized in digital electronic circuitry, integrated circuitry, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, and/or combinations thereof. These various implementations can include implementations in one or more computer programs that are executable and/or interpretable on a programmable system, including at least one programmable processor, which may be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

These computer programs (also known as programs, software, software applications or code) include machine instructions for a programmable processor, and can be implemented in a high-level procedural and/or object-oriented programming language, and/or in assembly/machine language. As used herein, the term “machine-readable medium” refers to any computer program product, apparatus and/or device (e.g., magnetic discs, optical disks, memory, Programmable Logic Devices (PLDs)) used to provide machine instructions and/or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term “machine-readable signal” refers to any signal used to provide machine instructions and/or data to a programmable processor. The machine-readable signal(s) may be non-transitory waves and/or non-transitory signals.

Although users have been described as a human, a user may be a person, a group of people, a person or persons interacting with one or more computers, and/or a computer system.

It is to be understood the implementations are not limited to particular systems or processes described which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular implementations only, and is not intended to be limiting. As used in this specification, the singular forms “a”, “an” and “the” include plural referents unless the content clearly indicates otherwise. Thus, for example, reference to “a setting” includes a combination of two or more settings and reference to “a fan” includes different types and/or combinations of fans.

Although the present disclosure has been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. 

1. An air conditioner system comprising: more than one compressor; more than one fan, wherein at least one of the fans comprises one or more first fans, and wherein a first fan comprises a high setting and one or more lower settings; a memory storing a fan management module; and a processor adapted to execute the fan management module, wherein the fan management module is adapted to: receive a request for operation of an air conditioner; determine a temperature proximate at least a portion of the air conditioner; and determine whether the determined temperature is less than a first predetermined low ambient temperature; if the determined temperature is less than the first predetermined low ambient temperature, restrict operation of at least one of the fans; and if the determined temperature is less than the first predetermined low ambient temperature, allow operation of at least one of the first fans.
 2. The system of claim 1, wherein the one or more lower settings comprises a first low setting; and wherein the fan management module is further adapted to: determine an operation of the compressors; determine whether the determined temperature is less than a second predetermined low ambient temperature, wherein the second predetermined low ambient temperature is less than the first predetermined low ambient temperature; and if the determined temperature is less than the second predetermined low ambient temperature and if the determined compressor operation comprises a full load operation, allow operation of at least one first fan at the first low setting.
 3. The system of claim 1, wherein the one or more lower settings comprises a first low setting, a second low setting that is lower than the first low setting, and a third low setting that is lower than the second low setting; and wherein the fan management module is further adapted to: determine an operation of the compressors; determine whether the determined temperature is less than a second predetermined low ambient temperature, wherein the second predetermined low ambient temperature is less than the first predetermined low ambient temperature; and if the determined temperature is less than the second predetermined low ambient temperature and if the determined compressor operation comprises a part load operation, allow operation of at least one first fan at the third low setting.
 4. The system of claim 1, wherein the one or more lower settings comprises a first low setting, a second low setting that is lower than the first low setting, and a third low setting that is lower than the second low setting; and wherein the fan management module is further adapted to: determine an operation of the compressors; determine whether the determined temperature is less than a second predetermined low ambient temperature; and if the determined temperature is less than the first predetermined low ambient temperature and the determined temperature is not less than the second predetermined low ambient temperature and the determined compressor operation comprises a part load operation, allow operation of at least one first fan at the second low setting.
 5. The system of claim 1, wherein the fan management module is further adapted to allow operation of one of the first fans and restrict operation of the other fans.
 6. The system of claim 1, wherein the fan management module is further adapted to: determine an operation of the compressors; and allow operation of at least one of the fans at the high setting if the determined compressor operation comprises a full load operation.
 7. The system of claim 1, wherein the one or more lower settings comprises a first low setting and a second low setting that is lower than the first low setting; and wherein the fan management module is further adapted to: determine an operation of the compressors; and allow operation of at least one of the fans at the second low setting if the determined compressor operation comprises a part load operation.
 8. The system of claim 1, wherein the fan management module is further adapted to: determine whether a compressor operation comprises a part load operation; and allow operation of one or more crankcase heaters associated with one or more compressors in which operation is restricted, if the compressor operation comprises a part load operation.
 9. The system of claim 1, wherein the fan management module is further adapted to: determine whether the determined temperature is less than a second predetermined low ambient temperature, wherein the second predetermined low ambient temperature is less than the first predetermined low ambient temperature; and allow operation of one or more crankcase heaters associated with one or more compressors of the air conditioner, if the determined temperature is less than the second predetermined low ambient temperature.
 10. A method comprising: determining a temperature proximate at least a portion of an air conditioner; determining whether the determined temperature is less than a first predetermined low ambient temperature; if the determined temperature is less than the first predetermined low ambient temperature, restricting operation of at least one fan of the air conditioner; and if the determined temperature is less than the first predetermined low ambient temperature, allowing operation of at least one of the fans of the air conditioner.
 11. The method of claim 10, wherein one or more fans of the air conditioner comprises a high setting and at least one low setting, and further comprising: determining whether the determined temperature is less than a second predetermined low ambient temperature; and allowing operation of at least one of the fans at one of the low settings, if the determined temperature is less than the second predetermined low ambient temperature.
 12. The method of claim 10, wherein one or more fan of the air conditioner comprises a high setting and at least one low setting, and further comprising: determining an operation of compressors of the air conditioner; determining whether the determined temperature is less than a second predetermined low ambient temperature; and allowing operation of at least one of the fans at the high setting, if the determined compressor operation comprises a full load operation, and if the determined temperature is less than the first predetermined low ambient temperature and not less than the second predetermined low ambient temperature.
 13. The method of claim 10, wherein one or more of the fans of the air conditioner comprises a high setting and at least one low setting, and further comprising: determining an operation of compressors of the air conditioner; and allowing operation of at least one of the fans of the air conditioner at one of the low settings if the determined compressor operation comprises a part load operation, and if the determined temperature is less than the first predetermined low ambient temperature.
 14. The method of claim 13, further comprising: allowing operation of one or more crankcase heaters associated with one or more of the compressors in which operation is restricted, if the determined operation of the compressors comprises a part load operation, and if the determined temperature is less than the first predetermined low ambient temperature.
 15. The method of claim 10, further comprising: determining whether the determined temperature is less than a second predetermined low ambient temperature, wherein the second predetermined low ambient temperature is less than the first predetermined low temperature; and allowing operation of one or more crankcase heaters associated with one or more of the compressors of the air conditioner, if the determined temperature is less than the second predetermined low ambient temperature.
 16. The method of claim 10, further comprising: determining an operation of compressors of the air conditioner; and allowing operation of one or more crankcase heaters associated with one or more of the compressors in which operation is restricted, if the determined temperature is less than the first predetermined low ambient temperature and the determined operation of the compressors comprises a part load operation.
 17. A method comprising: determining a temperature of a portion of an air conditioner; retrieving a predetermined low ambient temperature from a memory of a computer; determining if the determined temperature is less than the retrieved predetermined low ambient temperature; and if the determined temperature is less than the predetermined low ambient temperature: restricting operation of at least one fan of the air conditioner; and allowing operation of at least one fan of the air conditioner at a setting to maintain a pressure of a portion of the air conditioner in a predetermined pressure range.
 18. The method of claim 17, further comprising determining the setting to maintain the pressure of the portion of the air conditioner based at least partially on the determined temperature.
 19. The method of claim 17, further comprising determining the setting to maintain the pressure of the portion of the air conditioner based at least partially on at least one of the determined temperature, a number of fans included in the air conditioner, a number of modes of operation of each fan of the air conditioner, or the predetermined pressure range.
 20. The method of claim 17, further comprising: determining whether an operation of compressors of the air conditioner comprises a part load operation; and allowing operation of one or more crankcase heaters associated with compressors in which operation is restricted, if the operation of compressors comprises a part load operation and if the determined temperature is less than the retrieved predetermined low ambient temperature. 